I used to work as a design engineer for a pressure vessel manufacturer - we used explosion bonding all the time to bond more expensive corrosion resistant layer

I used to work as a design engineer for a pressure vessel manufacturer - we used explosion bonding all the time to bond more expensive corrosion resistant layers to carbon steel backing parts. Example: In a shell and tube heat exchanger, the tubes might have some really reactive stuff in it so you might make the tube side out of indium , titanium, nickel, or even an expensive stainless steel like S32205/S31803. The shell side might just have river water for cooling, and can just be painted and have a sacrificial anode somewhere inside. The bulkhead where all the tubes penetrate (the "tubesheet") might be 6' (180cm) in diameter and 4-8 inches (10-20cm) thick - an extraordinarily expensive hunk of material (or possibly not even available in the thickness needed) when made 100% of the more exotic materials; easily in the 6 figure range. Sometimes this problem is solved by having a welder coat the entire surface with weld metal that's good enough to withstand the corrosion characteristics of the process stream, but with larger parts this can take _days_; with some metallurgies (e.g. brass) it's not even possible. Instead, the practice was to explosion bond a "thin" layer (1/4" (6mm) or so) of the expensive stuff to a more standard carbon steel forging. The tubes are usually very thin walled and welded/brazed to the cladding. What's cool is the interface layer between the two metals looks like when two liquids meet with swirls and whorls of the two materials interleaving, but frozen solid.